The present disclosure relates to fluid powered pumps and more specifically to aspirator pumps.
An aspirator, or aspirator pump, uses one fluid to pump another fluid through the Venturi effect. A motivating fluid passing through a nozzle creates a vacuum drawing in a lower pressure fluid and causing a pumping effect. Aspirator pumps are commonly used in applications where mechanical pumps are not available or preferred. For example, aspirator pumps are used in situations where vibrations from a motor may be undesirable as in a laboratory or may be used in a medical procedure where suction pressure is desired. Aspirators may also be desirable where a source of energy in the form of liquid pressure is readily available, such as in steam or boiler systems. Aspirator pumps are also used when the combination of two streams of fluid is desired, such as in aircraft cooling systems.
Aspirator pumps in aircraft cooling systems have been used to draw excess air and water out of a low pressure source using a high pressure source of air or of air and water as a motivator. The motivating stream and the low pressure stream are combined in the aspirator. The combination of streams has been injected into heat exchangers to evaporate into a working stream of air near the inlet of a heat exchanger of an air conditioning system within an aircraft cooling system. This process increases the efficiency of the heat exchanger by cooling the air entering the heat exchanger.
This process is desirable not only to increase the efficiency of the heat exchanger, but to remove water from the system as the working air is eventually dumped overboard.